Operating mechanism for an electrical switch



April'2, 1968 I c. w. WOLF 3,375,723

I OPERATING MECHANISM FOR AN ELECTRICAL SWITCH Filed Aug. 25, 1966 2 Sheets-Sheet) INVENTOR.

(Zena/r2 14/ MZ/ April 2, 1968 c. w. WOLF 3,375,723

OPERATING MECHANISM FOR AN ELECTRICAL SWITCH Filed Aug. 25, 1966 2 Sheets-Sheet 2 INVENTOR.

United States Patent Ofiice 3,375,723 OPERATING MECHANISM FOR AN ELECTRICAL SWITCH Clement W. Wolf, 46020 Private Shore Drive, Mount Clemens, Mich. 48043 Filed Aug. 25, 1966, Ser. No. 574,962 Claims. (Cl. 74-100) This invention relates particularly to an operating mechanism for a switch featuring an operating spring that is housed within the manual operator of the operating mechanism.

The trend towards miniaturization of machine components has emphasized the need for an improved operating mechanism for an electrical switch of minimum size so as to minimize the total space requirement of the switch. In addition, such an operating mechanism must be capable of transmitting positive operating forces to the separable contacts of the switch so as to effect quick-make and quick-break movement thereof.

The aforesaid problems are solved, in accordance with the instant invention, by what isknOWn in the art as a front manual operator having an operating spring telescopically housed therein. Movement of the manual operator from the off to the on condition or from the on to the off condition efiects compression of the telescopically housed spring within the manual operator. Compression of the spring is elTected by a reciprocable rod which, upon movement of the manual operator, drives a crank lever towards a dead center position defined by a detent on the perimeter of a circular portion of a reciprocable arm. Further rotation of the manual operator effects further extension of the reciprocable rod and movement over and past the detent which is accommodated by elongated bearing slots in a crank lever. The detent feature requires additional eflfort be applied to the manual operator to move the manual operator through the dead center position. Spring pressure is transmitted by the reciprocable rod to the crank lever thence to a pin extending between a pair of reciprocable arms.

After the manual operator moves through the dead center position the spring force acting on the arm pin drives it to the opposite end of an elongated slot in supporting side plates thus moving the reciprocable arms to either the fully extended or fully retracted position.

In an exemplary embodiment of the instant invention, the reciprocable arms are coupled to the movable contacts of for example a contactor. It is to be noted, however, that it is within the concept of the instant invention that the subject operating mechanism is usable with other forms of switches and mechanisms motion.

Accordingly, one object of the instant invention is an improved operating mechanism for a switch.

Another object is an operating mechanism for a switch having an operating spring housed within a front manual operator.

Other objects and advantages of the instant invention will be apparent in the following description, claims, and drawings wherein:

FIGURE 1 is a plan view of the operating mechanism of the instant invention;

FIGURE 2 is a cross sectional view taken substantially along the line 22 of FIGURE 1;

FIGURE 3 is a cross sectional view similar to FIG- URE 2 of the manual operator in the opposite position;

FIGURE 4 is a cross sectional view taken substantially along the line 4-4 of FIGURE 2; and

FIGURE 5 is a cross sectional view taken along the line 55 of FIGURE 1.

As seen in the drawings, the operating mechanism requiring an on-oflfsubstantially generally to switches and more.

3,3 75,723 Patented Apr. 2 1968 of the instant invention is shown in operative association with a switch. The operating mechanism 10 comprises a tubular handle or manual operator 12 having a closed end portion 14 and an open end portion 16 threadably engaged with a bearing block 18. The bearing block 18 has a longitudinal bore 20 therein for journaling of a reciprocable rod 22. The block 18 is supported for rotation about a lateral axis bp a pair of pins 23 and 24 (FIG. 4).

The rod 22 is provided with a collar 26 at its upper end that is secured in position by pin 28 for the seating of one end of an operating spring 30. The spring 30 extends between the collar 26 and the bearing block 18. Thus, downward movement of the reciprocable rod 22, as shown in dotted lines in FIGURES 2 and 3 of the drawings, effects compression of the spring 30.

A lower end portion 36 of the rod 22 is threadably engaged in a crank pin block 38 which has a transverse bore 40 therein for the acceptance of a crank pin 42. A pair of crank levers 44 and 46 (FIG. 4) are supported on end portions 48 and 50 of the crank pin 42, respectively, opposite ends thereof being provided with elongated slots 50 and 52 for the acceptance of a pair of pins 54 and 56, respectively. The pins 54 and 56 extend through complementary apertures 58 and 60 in a pair of reciprocable arms 62 and 64, respectively, to effect reciprocable movement of said arms, as will be described. Suitable spacers 66 and 68 are disposed between the reciprocable arms 62 and 64 and their respective crank levers 44 and 46.

The pins 54 and 56 are slidable in complementary slots 70 and 72 in side plates 74 and 76, respectively, of the operating mechanism.

As best seen in FIGURE 5 of the drawings, a contactor assembly suitable for use with the operating mechanism of the instant invention comprises a pair of contacts and 102 having suitable terminals 104 and 106, respectively. A circuit is completed between the contacts 100 and 102 by a contact bar 108 that is mounted on a pin 110. The pin 110 is j-ournaled in an insulating support 112, a spring 114 providing the necessary lost motion to effect contact pressure. The insulating assembly 112 is secured to suitable plates 116 which in turn are secured to the arms 62 and 64 by a pin 118. Thus, reciprocation of the arms 62 and 64 effects engagement and disengagement of the contact bar 108 with the contacts 100 and 102, as well as the other contacts of the contactor 10, thereby to make and break an electrical circuit.

In operation, moving operator 12 from off to on or on to off, rotates the crank levers 44 and 46 by means of the crank pin 42, compressing the spring 30 due to downward movement of the reciprocable rod 22 because of difierent centers of rotation. As the manual oper ator 12 drives the crank levers 44 and 46 toward the dead center position, a hump or detent 120 on the perimeter of the circular portion of the reciprocable arms 62 and 64 cams the crank pin 42 downwardly, as seen in the drawings, to further extend the reciprocable rod 22 and further compress the spring 30 and thus requiring added effort to move the manual operator 12 through the dead center position. This additional downward movement of the rod 22 and crank levers 44 and 46 is accommodated by the elongated bearing holes 50 and 52 in the pivotal end of the crank levers 44 and 46.

Spring pressure, transmitted by the reciprocable rod 22 and crank levers 44 and 46 to pins 54 and 56 anchored to the reciprocable arms 62 and 64 forces the pins to the opposite end of the elongated slots 70 and 72 in supporting side plates 74 and 76 thus moving the reciprocable arms 62 and 64 to either the fully extended or fully retracted position.

The reciprocable arms 62 and 64 are coupled to the contact 108 as discussed hereinbefore.

It is to be noted that another feature of the instant invention is the manner of retaining the spring 30 so that no pressure is exerted on the closed end 14 of the handle or manual operator 12. This is a desirable safety feature on larger switches requiring high operating spring pressures.

While it will be apparent that the preferred embodiments of the invention disclosed are well calculated to fulfill the objects above stated, it will be appreciated that the invention is susceptible to modification, variation, and change without departing from the proper scope or fair meaning of the subjoined claims.

What is claimed is:

1. An operating mechanism for an electrical switch or the like comprising,

an elongated tubular manual operator journaled for rotation about an axis extending transversely thereof,

a spring telescopically housed internally of said manual operator and compressible longitudinally thereof,

a crank lever,

a crank pin secured to one end of said crank lever,

a reciprocable rod having one end coupled to said spring and an opposite end rotatably coupled to said crank pin,

a reciprocable arm,

means for rotatably coupling an opposite end of said crank lever to said reciprocable arm, and

support means for guiding said arm for reciprocable movement under the bias of said spring. 2. An operating mechanism for an electrical switch or the like as recited in claim 1 wherein said reciprocable arm has a radially extending detent engageable by said crank pin to effect further com- 'pression of said spring. 3. An operating mechanism for an electrical switch or the like as recited in claim 2 wherein said crank lever has an elongated slot to permit radial movement of said crank pin over said detent to effect further compression of said spring. 4. An operating mechanism for an electrical switch or the like as recited in claim 1 wherein said coupling means comprises a pin receivable in said support means. 5. An operating mechanism for an electrical switch or the like as recited in claim 1 wherein said arm is connected to a movable contact of said switch.

References Cited UNITED STATES PATENTS 2,425,278 8/1947 Ericson 74100 2,754,688 7/1956 Barecki 74100 FRED C. MATTERN, 111., Primary Examiner. F. D. SHOEMAKER, Assistant Examiner. 

1. AN OPERATING MECHANISM FOR AN ELECTRICAL SWITCH OR THE LIKE COMPRISING, AN ELONGATED TUBULAR MANUAL OPERATOR JOURNALED FOR ROTATION ABOUT AN AXIS EXTENDING TRANSVERSELY THEREOF, A SPRING TELESCOPICALLY HOUSED INTERNALLY OF SAID MANUAL OPERATOR AND COMPRESSIBLE LONGITUDINALLY THEREOF, A CRANK LEVER, A CRANK PIN SECURED TO ONE END OF SAID CRANK LEVER, A RECIPROCABLE ROD HAVING ONE END COUPLED TO SAID SPRING AND AN OPPOSITE END ROTATABLY COUPLED TO SAID CRANK PIN, A RECIPROCABLE ARM, MEANS FOR ROTATABLY COUPLING AN OPPOSITE END OF SAID CRANK LEVER TO SAID RECIPROCABLE ARM, AND SUPPORT MEANS FOR GUIDING SAID ARM FOR RECIPROCABLE MOVEMENT UNDER THE BIAS OF SAID SPRING. 